Modified analytical embedded-atom method simulation of the mono-vacancy at three low-index surfaces of BCC transition metals
WEN Yan-ni, ZHANG Jian-min
(College of Physics and Information Technology, Shaanxi Normal University, Xi′an 710062, Shaanxi, China)
Abstract:
The formation energies of mono-vacancy in the first nine layers of three low-index surfaces (100), (110) and (111) of BCC transition metals Fe、W、Mo、Cr、Ta、Nb and V have been calculated by using the Modified Analytical Embedded-atom Method (MAEAM). Relevant results can be obtained: for each metal, the minimum formation energies of mono-vacancy is on the top layer at each low-index surface, and the lower surface density implies the lower formation energies of mono-vacancy in the first layer and the second layer (excepting Nb), that is E(111)，11f＜E(100)，11f＜E(110)，11f and E(111)，21f＜E(100)，21f＜E(110)，21f. This indicates the formation of vacancy on the first layer is easier to occur than the other layers for the BCC transition metals, especially for the (111) surface.
KeyWords:
body-centered cubic (BCC); transition metals; vacancy; formation energy; modified analytical embedded-atom method (MAEAM)
